I recently started playing with [devstack][1] again (An all-in-on OpenStack developer setup). Last time was over 3 years ago because I remember a [pull request for a missing dependency][2] at the time.
The installation docs provide information to bootstrap your system with a [necessary user and privileges][3], however like many docs for software setup they contain one off instructions.
adduser stack echo "stack ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
When you write operations code you need to always be thinking about “testability” and “automation”. It is important to write re-runable code. You should always write parameterized code when possible, which can be refactored into usable functions at any time.
This is a good example to demonstrate a simple test condition for making the initial instructions re-runable.
sudo su -
NEW_USER="stack"
# This creates default group of same username
# This creates user with default HOME in /home/stack
[ `grep ${NEW_USER} /etc/passwd | wc -l` -eq 0 ] && useradd -s /bin/bash -m ${NEW_USER}
NEW_USER_SUDO_FILE="/etc/sudoers.d/${NEW_USER}"
[ ! -s ${NEW_USER_SUDO_FILE} ] && umask 226 && echo "${NEW_USER} ALL=(ALL) NOPASSWD: ALL" > ${NEW_USER_SUDO_FILE}
ls -l ${NEW_USER_SUDO_FILE}
[1]: http://docs.openstack.org/developer/devstack/
[2]: https://github.com/ronaldbradford/devstack/commit/59b3f402cd9a997836b03560c7d31cf96304ca1e
[3]: http://docs.openstack.org/developer/devstack/guides/single-machine.html
